diff --git a/src/main/java/com/zipcodewilmington/scientificcalculator/Console.java b/src/main/java/com/zipcodewilmington/scientificcalculator/Console.java
index eeb5ccc..13239c5 100644
--- a/src/main/java/com/zipcodewilmington/scientificcalculator/Console.java
+++ b/src/main/java/com/zipcodewilmington/scientificcalculator/Console.java
@@ -28,6 +28,10 @@ public static double multiply(double a, double b) {
     }
 
     public static double divide(double a, double b) {
+        if (b == 0) {
+            throw new ArithmeticException("Err");
+        }
+
         double quotient = a / b;
         System.out.println(quotient);
         return quotient;
@@ -40,6 +44,9 @@ public static double square(double a) {
     }
 
     public static double squareRoot(double a) {
+        if (a < 0) {
+            throw new ArithmeticException("Err");
+        }
         double result = Math.sqrt(a);
         System.out.println(result);
         return result;
@@ -58,6 +65,9 @@ public static double invert(double a) {
     }
 
     public static double logarithm(double a) {
+        if (a <= 0) {
+            throw new ArithmeticException("Err");
+        }
         double result = Math.log(a);
         System.out.println(result);
         return result;
@@ -69,7 +79,41 @@ public static double exponent(double a, double b) {
         return result;
     }
 
+    public static double sine(double a) {
+        double result = Math.sin(a);
+        System.out.println(result);
+        return result;
+    }
+
+    public static double cosine(double a) {
+        double result = Math.cos(a);
+        System.out.println(result);
+        return result;
+    }
+
+    public static double tangent(double a) {
+        double result = Math.tan(a);
+        System.out.println(result);
+        return result;
+    }
 
+    public static double inverseSine(double a) {
+        double result = Math.asin(a);
+        System.out.println(result);
+        return result;
+    }
+
+    public static double inverseCosine(double a) {
+        double result = Math.acos(a);
+        System.out.println(result);
+        return result;
+    }
+
+    public static double inverseTangent(double a) {
+        double result = Math.atan(a);
+        System.out.println(result);
+        return result;
+    }
 
     public static void print(String output, Object... args) {
         System.out.printf(output, args);
diff --git a/src/main/java/com/zipcodewilmington/scientificcalculator/MainApplication.java b/src/main/java/com/zipcodewilmington/scientificcalculator/MainApplication.java
index 77ff5e6..2e4473a 100644
--- a/src/main/java/com/zipcodewilmington/scientificcalculator/MainApplication.java
+++ b/src/main/java/com/zipcodewilmington/scientificcalculator/MainApplication.java
@@ -40,6 +40,24 @@ public static double  calculate(double a, double b, String operator) {
             case "exp":
                 result = (double) Console.exponent(a, b);
                 break;
+            case "sin":
+                result = (double) Console.sine(a);
+                break;
+            case "cos":
+                result = (double) Console.cosine(a);
+                break;
+            case "tan":
+                result = (double) Console.tangent(a);
+                break;
+            case "asin":
+                result = (double) Console.inverseSine(a);
+                break;
+            case "acos":
+                result = (double) Console.inverseCosine(a);
+                break;
+            case "atan":
+                result = (double) Console.inverseTangent(a);
+                break;
             default:
                 System.out.println("Invalid operator");
         }
@@ -50,19 +68,28 @@ public static double  calculate(double a, double b, String operator) {
     public static void main(String[] args) {
         boolean isRunning = true;
         double result = 0.0;
+        double memory = 0.0;
+        double prevA = 0.0;
+        double prevB = 0.0;
+        String prevOperator = "";
 
-        String prompt = "Enter an operator (+, -, *, /, sqrt, sqr, inv, neg, log, exp): ";
+        String prompt = "Enter an operator (+, -, *, /, sqrt, sqr, inv, neg, log, exp, sin, cos, tan, mr, cv, mc): ";
         String operatorInput = Console.getStringInput(prompt);
-        if (operatorInput.equals("sqrt") || operatorInput.equals("sqr") || operatorInput.equals("inv") || operatorInput.equals("neg") || operatorInput.equals("log")) {
+        if (operatorInput.equals("sqrt") || operatorInput.equals("sqr") || operatorInput.equals("inv") || operatorInput.equals("neg") || operatorInput.equals("log") || operatorInput.equals("sin") || operatorInput.equals("cos") || operatorInput.equals("tan")) {
             Double numInput = Console.getDoubleInput("Enter a number: ");
+            prevA = numInput;
+            prevB = 0.0;
+            prevOperator = operatorInput;
             result = calculate(numInput, 0, operatorInput);
             Console.println("Result: %f", result);
         } else {
-            
-        Double num1Input = Console.getDoubleInput("Enter the first number: ");
-        Double num2Input = Console.getDoubleInput("Enter the second number: ");
-        result = calculate(num1Input, num2Input, operatorInput);
-        Console.println("Result: %f", result);
+            Double num1Input = Console.getDoubleInput("Enter the first number: ");
+            Double num2Input = Console.getDoubleInput("Enter the second number: ");
+            prevA = num1Input;
+            prevB = num2Input;
+            prevOperator = operatorInput;
+            result = calculate(num1Input, num2Input, operatorInput);
+            Console.println("Result: %f", result);
         }
 
         while (isRunning) {
@@ -71,23 +98,42 @@ public static void main(String[] args) {
         if (again.equalsIgnoreCase("no")) {
             isRunning = false;
         } else {
-            String newOperator = Console.getStringInput("Enter an operator (+, -, *, /, sqrt, sqr, inv, neg, log, exp): ");
+            String newOperator = Console.getStringInput("Enter an operator (+, -, *, /, sqrt, sqr, inv, neg, log, exp, sin, cos, tan, mr, cv, mc): ");
 
-            if (newOperator.equals("sqrt") || newOperator.equals("sqr") || newOperator.equals("inv") || newOperator.equals("neg") || newOperator.equals("log")) {
+            if (newOperator.equals("mr")) {
+                result = memory;
+                Console.println("Memory Recall: %f", result);
+            } else if (newOperator.equals("cv")) {
+                Console.println("Current Value: %f", result);
+            } else if (newOperator.equals("mc")) {
+                memory = 0.0;
+                Console.println("Memory cleared.");
+            } else if (newOperator.equals("redo")) {
+                Double editNum = Console.getDoubleInput("Enter a new number: ");
+                memory = result;
+                result = calculate(prevA, editNum, prevOperator);
+                Console.println("Result: %f", result);
+            }            
+            else if (newOperator.equals("sqrt") || newOperator.equals("sqr") || newOperator.equals("inv") || newOperator.equals("neg") || newOperator.equals("log") || newOperator.equals("sin") || newOperator.equals("cos") || newOperator.equals("tan")) {
+                memory = result;
+                prevA = result;
+                prevB = 0.0;
+                prevOperator = newOperator;
                 result = calculate(result, 0, newOperator);
-            } else {
+                Console.println("Result: %f", result);
+            }
+            else {
                 Double newNum = Console.getDoubleInput("Enter a number: ");
+                memory = result;
+                prevA = result;
+                prevB = newNum;
+                prevOperator = newOperator;
                 result = calculate(result, newNum, newOperator);
+                Console.println("Result: %f", result);
             }
-            Console.println("Result: %f", result);
         }
         }
         Console.println("Thank you for using the calculator!");
     }
 }
 
-
-//             String newOperator = Console.getStringInput("Enter an operator (+, -, *, /): ");
-//             Double newNum = Console.getDoubleInput("Enter a number: ");
-//             double newResult = calculate(result, newNum, newOperator);
-//             result = newResult;
\ No newline at end of file